RCOV Dependency clashing with Ruby 1.9.x and 2.x switch to simplecov needed

[rennhak]

Dm-sweatshop depends on Rcov. Rcov is not compatible with Ruby 1.9.x or 2.x hence they recommend to use simple-cov instead of Rcov. Dm-sweatshop depends on Rcov, but this will not work on mentioned Ruby versions resulting in a fatal gem install clash when installed directly.

Currently I resolved this issue by installing simplecov-rcov first which provides the env.h for the error "fatal error: env.h: No such file or directory", hence doesn't try to install rcov anymore.